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All the time, otherwise you'd buy the 35mm F2 and save about $1.2k. Depth of Field is a function of Aperture , Focal Length and Distance to plane of focus. Th

All the time, otherwise you'd buy the 35mm F2 and save about $1.2k. Depth of Field is a function of Aperture , Focal Length and Distance to plane of focus. The focal length drives how wide the "scatter" of the blur is, so wide angle lenses like the 35mm have a very "soft" blur as opposed to something like a 400mm F2.8 which just obliterates backgrounds. This is also driven by how close you are focusing so you can shoot a 35mm F1.4 wide open, focusing around ~15ft away and the detail of the scene is very much preserved. It lets you focus on a subject and give them a slight "pop" of focus while keeping the rest of scene coherent.

foldr 11y ago
Can you give an example of the sort of scene you have in mind? I often play around with 4x5 photography, where it would be trivially easy to get that effect for a subject 15ft away with a $100 lens, but I've never actually wanted to do it.
- vvanders 11y ago
  Yeah, in 4x5 you've got a larger "sensor" which also contributes to DoF. [edit] If I remember my lens geometry correctly, film size is just the other side of focal length when it comes to bokeh calculations. I grabbed this random image from the 35L group on Flickr, they didn't include EXIF so I can't be 100% certain they shot it at F1.4 but it looks very close to shots I have at F1.4 from that lens. https://www.flickr.com/photos/49830238@N04/25021998886/in/pool-27449914@N00/ https://www.flickr.com/photos/49830238@N04/25021998886/in/po...
  - foldr 11y ago
    >Yeah, in 4x5 you've got a larger "sensor" which also contributes to DoF. It’s only the focal length and aperture that contribute to DoF. With a larger sensor you are typically using longer focal lengths since you need a longer focal length to get the same FoV. That being said, you also have the option of using movements on 4x5, so subject separation can be achieved by changing the plane of focus even when using a narrow aperture. There are some very technically accomplished examples of this at http://www.p1600.com/en/portfolio/london_5x4/ http://www.p1600.com/en/portfolio/london_5x4/ (not my photos), but on balance I think that these are more of a technical tour de force than an artistic success. There's no way to know what aperture the photo you linked to was shot at, but it doesn't look to me like it would have to be particularly wide. Honestly, I find it a bit depressing that there are flickr groups fetishizing particular lenses.
    - vvanders 11y ago
      4x5 is a whole nother beast though. We're talking about SLRs and fixed-lens cameras. Usually you don't get any movements and very little options on that front unless you're using a TS-E. Don't see any reason why the one I picked wouldn't be shot at F1.4. Anyway, here's another random one that does have EXIF that shows what I mean. Just because you're shooting at F1.4 doesn't mean that everything is blown away. https://www.flickr.com/photos/jasoncowellphoto/5534870906 https://www.flickr.com/photos/jasoncowellphoto/5534870906 I guess you can call if "fetishizing" a lens if you want but it's a very popular lens for a reason.
      - foldr 11y ago
        Hmm, the second photo is a case where everything is pretty much at infinity, so the only significant consequence of using a very wide aperture is that you’re letting more light in. (Yeah, you can see that the background is very slightly out of focus compared to the bikes, but the defocusing is so slight that it looks more like a mistake than a deliberate effect.) Plus, look, I know that you didn't choose the photo for it's artistic qualities, but that photo sucks, and the comments on it are like "omg you have a 35L and the photos are sharp". Who the fuck cares if the photos are bad? The vast majority of the photos in the group either have (i) pretty much everything in the picture in acceptably sharp focus (so that even if they were shot at f1.4, they didn’t have to be) or (ii) a close subject (so that a very wide aperture was not necessary to get good separation). Is it possible to imagine scenarios where you need f1.4 to obtain the desired effect? Yeah, sure. But they’re precisely the scenarios that rarely lead to good compositions. I.e., middle ground in focus and foreground and background out of focus.

foldr 11y ago

Can you give an example of the sort of scene you have in mind? I often play around with 4x5 photography, where it would be trivially easy to get that effect for a subject 15ft away with a $100 lens, but I've never actually wanted to do it.

vvanders 11y ago
Yeah, in 4x5 you've got a larger "sensor" which also contributes to DoF. [edit] If I remember my lens geometry correctly, film size is just the other side of focal length when it comes to bokeh calculations. I grabbed this random image from the 35L group on Flickr, they didn't include EXIF so I can't be 100% certain they shot it at F1.4 but it looks very close to shots I have at F1.4 from that lens. https://www.flickr.com/photos/49830238@N04/25021998886/in/pool-27449914@N00/ https://www.flickr.com/photos/49830238@N04/25021998886/in/po...
- foldr 11y ago
  >Yeah, in 4x5 you've got a larger "sensor" which also contributes to DoF. It’s only the focal length and aperture that contribute to DoF. With a larger sensor you are typically using longer focal lengths since you need a longer focal length to get the same FoV. That being said, you also have the option of using movements on 4x5, so subject separation can be achieved by changing the plane of focus even when using a narrow aperture. There are some very technically accomplished examples of this at http://www.p1600.com/en/portfolio/london_5x4/ http://www.p1600.com/en/portfolio/london_5x4/ (not my photos), but on balance I think that these are more of a technical tour de force than an artistic success. There's no way to know what aperture the photo you linked to was shot at, but it doesn't look to me like it would have to be particularly wide. Honestly, I find it a bit depressing that there are flickr groups fetishizing particular lenses.
  - vvanders 11y ago
    4x5 is a whole nother beast though. We're talking about SLRs and fixed-lens cameras. Usually you don't get any movements and very little options on that front unless you're using a TS-E. Don't see any reason why the one I picked wouldn't be shot at F1.4. Anyway, here's another random one that does have EXIF that shows what I mean. Just because you're shooting at F1.4 doesn't mean that everything is blown away. https://www.flickr.com/photos/jasoncowellphoto/5534870906 https://www.flickr.com/photos/jasoncowellphoto/5534870906 I guess you can call if "fetishizing" a lens if you want but it's a very popular lens for a reason.
    - foldr 11y ago
      Hmm, the second photo is a case where everything is pretty much at infinity, so the only significant consequence of using a very wide aperture is that you’re letting more light in. (Yeah, you can see that the background is very slightly out of focus compared to the bikes, but the defocusing is so slight that it looks more like a mistake than a deliberate effect.) Plus, look, I know that you didn't choose the photo for it's artistic qualities, but that photo sucks, and the comments on it are like "omg you have a 35L and the photos are sharp". Who the fuck cares if the photos are bad? The vast majority of the photos in the group either have (i) pretty much everything in the picture in acceptably sharp focus (so that even if they were shot at f1.4, they didn’t have to be) or (ii) a close subject (so that a very wide aperture was not necessary to get good separation). Is it possible to imagine scenarios where you need f1.4 to obtain the desired effect? Yeah, sure. But they’re precisely the scenarios that rarely lead to good compositions. I.e., middle ground in focus and foreground and background out of focus.